Intra and intercellular events related to the control of prostate cell growth and cell division exerted by androgens are being studied at 2 levels of complexity. (a) Examining evidence for interactions between rat ventral prostate epithelial and connective tissue cells by cultivating these separated cell types obtained from normal or hormonally manipulated rats, either alone or in combination. (b) Effects of androgens on the composition and function of DNA replication complexes isolated by a procedure originally used to separate prostate "euchromatin". Because of ready access to human breast cancer samples, and responsibility for estrogen and progesterone receptor measurements on this material, studies with these receptors relevent to prostate steroid hormone receptors are being performed. Lastly, in view of the work concerning protein synthesis intrinsic to cell nuclei that has been done and the availability of a Chinese hamster ovary cell line (tsH1) with a temperature-sensitive defect in cytoplasmic non-mitochondrial protein synthesis, this cell line is being used to examine protein synthesis intrinsic to cell nuclei.